Dump valve

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c200Kompressor

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Joined
Jun 6, 2007
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170
Location
Portugal
Car
Toyota Yaris 1.0 VVT-I and C200 kompressor
Hello! It's possible to put a dump valve on a C200 kompressor? And what's the point of a dump valve?
 
Holds back 'things' until a convenient time to is found to 'go'.....





Ah, no, you mean a dump valve on a turbocharged engine....;)

It allows intake manifold air to be bled off to allow the turbo to keep spinning on a petrol engined car with throttle flaps, that stall the turbo and cause turbo lag when changing gear..

Not necessary on either a supercharged, automatic or diesel car.
 
hi i am interested in this as well

yes its not necessary on supercharged or diesel cars - but there is no harm in adding as it sounds much better with it on

also they cost next to nothing

i have a c200k as well - and am interested to get it down

any thoughts
 
No! It will sound barry!
 
... its not necessary on ... diesel cars - but there is no harm in adding as it sounds much better with it on

Won't it still sound like a diesel - ie bad?
 
If you want your Merc to go pssssssssssssssssssht every few mins you could always buy an Atego and get it as standard :D:doh::wallbash:
 
A dump valve is only needed on a turbo with megga boost as when you let go of the throttle the turbo is still spinning and pushing air into the intake system. This causes the turbo to effectively stall as it is trying to push against a closed throttle. This causes the turbine (exhaust side) to effectively stop (same shaft as compressor). This causes back pressure in the exhaust which is very bad, as the hot gasses are trapped in the head.
On a supercharged engine you don't have any turbines in the exhaust hence no back pressure to worry about.
One thing to be very careful of is fitting a dump valve means that the fuel system has accurately measured the correct amount of fuel for the amount of air that has been drawn in. By dumping air the air fuel ratio is now very wrong!!!!

Effectively the dump valve has removed air so way too much petrol will be added to the combustion chambers and will lead to a very rich mixture and thus damage your catalytic converter very quickly.

So basically if you want to replace your cat for each MoT fit a dump valve!!!!!!

Advice is DONT DO IT.

Hope that give you something to think about?
 
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Hello! It's possible to put a dump valve on a C200 kompressor? And what's the point of a dump valve?

On a production vehicle, it's main purpose is noise supression. ;)

No requirement for one on a non positive displacement device like a roots supercharger.
 
don't all turbocharged cars (petrol or diesel) have them as standard anyway?

Hmm - mind you there isn't a throttle body on a diesel is there.

Not noticed it on my c220 but when driving my wifes VW TDi in the summer with the window down there, you could hear the turbo whistle as it picked up pressure but on each gear change there was a faint "tsss" noise - I assumed it was some sort of pressure release valve - what else could make that noise?
 

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